From 4f143539f8c0264ef4175356110c05e346a847f2 Mon Sep 17 00:00:00 2001
From: Klaus Basan <klaus.basan@klausbasan.de>
Date: Sun, 13 May 2018 12:22:52 +0200
Subject: [PATCH] Fixed unit tests

* Random number generation was faulty, as we have to use RAND_MAX and not INT_MAX
* fixed CTestAircraftSituation::testSetRotateUpPitch, we need to use a defined front function otherwise it can be randomly outside range
* adjusted performance unit test a bit, as the value vary a lot


Ref T261
---
 src/blackmisc/math/mathutils.cpp           | 13 +++++++++----
 tests/blackmisc/testaircraftsituation.cpp  |  7 +++++++
 tests/blackmisc/testinterpolatorlinear.cpp |  5 ++++-
 3 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/src/blackmisc/math/mathutils.cpp b/src/blackmisc/math/mathutils.cpp
index efe0e6070..ddc9dba89 100644
--- a/src/blackmisc/math/mathutils.cpp
+++ b/src/blackmisc/math/mathutils.cpp
@@ -100,20 +100,25 @@ namespace BlackMisc
         int CMathUtils::randomInteger(int low, int high)
         {
             static QThreadStorage<uint> seeds;
+            Q_ASSERT_X(high < INT_MAX, Q_FUNC_INFO, "Cannot add 1");
+            Q_ASSERT_X(low >= 0 && high >= 0, Q_FUNC_INFO, "Only valid for positive values");
+            Q_ASSERT_X(high <= RAND_MAX, Q_FUNC_INFO, "RAND_MAX exceeded");
             if (!seeds.hasLocalData())
             {
                 // seed is per thread!
-                uint seed = static_cast<uint>(QTime::currentTime().msec());
+                const uint seed = static_cast<uint>(QTime::currentTime().msec());
                 qsrand(seed);
                 seeds.setLocalData(seed);
             }
-            int r(qrand());
-            return r % ((high + 1) - low) + low;
+            const int r(qrand());
+            const int mod = (high + 1) - low;
+            return (r % mod) + low;
         }
 
         double CMathUtils::randomDouble(double max)
         {
-            static const int MAX(INT_MAX);
+            // on Win system, RAND_MAX is only 16bit, on other systems higher
+            static const int MAX(RAND_MAX < INT_MAX ? RAND_MAX : INT_MAX - 1);
             const double r = randomInteger(0, MAX);
             return (r / MAX) * max;
         }
diff --git a/tests/blackmisc/testaircraftsituation.cpp b/tests/blackmisc/testaircraftsituation.cpp
index 069451777..7addb3ad4 100644
--- a/tests/blackmisc/testaircraftsituation.cpp
+++ b/tests/blackmisc/testaircraftsituation.cpp
@@ -228,13 +228,20 @@ namespace BlackMiscTest
     CAircraftSituationList CTestAircraftSituation::testSetRotateUpPitch(const CAircraftSituationList &situations)
     {
         CAircraftSituationList newSituations;
+        double average = 0;
         for (const CAircraftSituation &situation : situations)
         {
             CAircraftSituation s(situation);
             const double pitch = CMathUtils::randomDouble(1.5);
+            average += pitch;
             s.setPitch(CAngle(pitch, CAngleUnit::deg()));
             newSituations.push_back(s);
         }
+        average = average / newSituations.size();
+        CAircraftSituation avg = newSituations.front();
+        avg.setPitch(CAngle(average, CAngleUnit::deg()));
+        avg.addMsecs(1000); // make this the latest situation
+        newSituations.push_front(avg); // first value is average pitch, so it will NOT be detected
         return newSituations;
     }
 
diff --git a/tests/blackmisc/testinterpolatorlinear.cpp b/tests/blackmisc/testinterpolatorlinear.cpp
index 96a767427..9d787a5d7 100644
--- a/tests/blackmisc/testinterpolatorlinear.cpp
+++ b/tests/blackmisc/testinterpolatorlinear.cpp
@@ -134,8 +134,11 @@ namespace BlackMiscTest
                 interpolationNo++;
             }
         }
+
+        // check on time just to learn if interpolation suddenly gets very slow
+        // this is a risky test as in some situations the values can be exceeded
         int timeMs = timer.elapsed();
-        QVERIFY2(timeMs < interpolationNo, "Interpolation > 1ms");
+        QVERIFY2(timeMs < interpolationNo * 1.5, "Interpolation > 1.5ms");
         qDebug() << timeMs << "ms" << "for" << interpolationNo << "interpolations";
 
         int fetchedParts = 0;